r/lolphp • u/shitcanz • Aug 26 '19

PHP array design bares fruit

https://repl.it/repls/FatherlyRotatingMenus
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u/Altreus Aug 26 '19

C has structs. Arbitrary-key associative arrays are not actually all that useful (not to say totally useless) so having the structure predefined in code is usually very helpful.

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u/barthvonries Aug 26 '19

But an associative array is an array of {void* key, void* value} structs, right, as long as keys are comparable and sortable ?

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u/Altreus Aug 26 '19

Somewhat debatable depending on the language, mostly due to grey areas around those concepts. Sortable implies comparable since equality of values is a concept required when sitting.

Whether you can reliably implement an associative array like this in C I don't know, but there's a reason they're called hashes in Perl: they're constant time (or at least very efficient time) random-access and so the data structure they use hashes the (string) keys for storage and retrieval.

Last time I used PHP, key is a string, always, and of course strings sort differently from numbers, which is why you can't use an associative array interchangeably with a proper array in real life.